Trueshaft

ABSTRACT

Disclosed is a golf shaft comprising a plurality of sides imparting a desired flexibility and rigidity to a golf club, such that the golf club possesses desired flexibility and necessary rigidity to enable the club to carry through and provide optimal flight to a golf ball.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to golf shafts and, more specifically, to golf shafts possessing a plurality of sides for desired flexibility.

2. Description of the Prior Art

Generally, when a golf ball is struck, the ball is flattened or compressed slightly due to its resilient nature, and compression ultimately results in a kickback against the club head. This particular action controls the length of the flight rather than the force of blow.

Club head misalignment can be influenced by controlling the torsional stiffness of the shaft. The torsional stiffness of the shaft resists the twisting of the club head during the swing and particularly when there is less than centered contact between the ball and head. Shafts having high torsional stiffness are available in the marketplace and are generally know as low torque shafts.

One disadvantage of conventional low torque shafts is that a sacrifice in bending stiffness and weight is made in order to enhance torsional stiffness. That is, torsional resistance and bending stiffness are both increased in conventional low torque shafts. Bending stiffness provides the trajectory of the ball, the feel of the club, and contributes to the distance resulting from each hit. In general, shafts with a low bending stiffness are desirable for most golf shots.

Further, there are numerous factors which affect the performance characteristics of golf shaft such as weight and balance of the shaft, the flexibility of the shaft and the ability to withstand shock.

Moreover, an intangible aspect of the golf shaft referred to as “feel” also has a definite effect on the playability of the shaft as well as the commercial acceptance of the shaft. Presently, a variety of golf shafts are manufactured from materials such as wood, titanium steel or aluminum. Further, most of the golf shafts today available in the market are circular in cross section.

As explained in U.S. Pat. No. 4,984,794, a golf club is provided. The golf club of this patent includes a shaft having a means for supporting a head and a head for attachment to the shaft, the head having means for engaging the supporting means of the shaft. The supporting means is rigidly affixed to the shaft. The supporting means of the shaft and the engaging means of the head include means for selectively positioning the shaft at one of a plurality of predetermined angles relative to the head as the shaft and the head are attached.

The shaft of the golf club in this patent further includes an external assembly part and the supporting means of the shaft includes an internal surface area of the external assembly part. The head includes an internal assembly part and the engaging means of the head includes an external surface area of the internal assembly part such that the internal assembly part is receivable within the external assembly part. In addition, the engaging means of the head includes means for engaging only a predetermined portion of the internal surface area of the external assembly part which varies in response to which of the plurality of predetermined angles the shaft is attached relative to the head.

In U.S. Pat. No. 4,319,750, a gold shaft is provided. The golf shaft explained in this patent is constructed in such a manner that it provides an impedance mismatch at a predetermined point along its length which determines the position of the flex zone along the shaft. The impedance mismatch relates to the shock wave that travels up the shaft when a ball is struck and results in golf club shafts fabricated with predetermined “feel” and flex characteristics. For instance, better golfers prefer shafts with a high flex zone, measured from the heel of the club head, whereas high handicapped golfers appear to derive greater benefits from clubs with shafts having a so-called lower flex point or zone, i.e., a flex point that is located closer to the heel of the golf club head. Accordingly, the golf shaft constructed in such a way that the “feel” and flexing characteristics of the shaft are predetermined and controlled during manufacture.

In U.S. Pat. No. 5,665,010, a composite golf shaft is provided. The composite golf club shaft explained in this patent is constructed to modify the flex pattern of the shaft. Rather than providing a substantially constant flexing arc over the length of the shaft between the hand grip and the club head, the flexing characteristics of this shaft are modified so that the portion of the shaft adjacent the hand grip, and extending toward the club head, is stiffened so is resistant to flexing, leaving a shorter portion of the shaft toward the club head to flex. The club shaft is constructed so that a portion of the shaft extending between about fifteen inches to about eighteen inches from the hand grip end of the shaft resists bending or flexing during swing of the club, with the remaining portion of the shaft toward the club head flexing during swing. The shorter flexing portion of the club shaft reduces the twisting or torque of the club head which takes place.

The above shafts possess a variety of disadvantages such as transferring vibrational shocks to the player when the ball is struck during play and does not impart the desired flexibility and rigidity. Some are subject to change in physical characteristics in response to climatic changes.

In light of the foregoing discussion, there is a need for an improved golf shaft which overcomes the problem posed by the existing golf shaft. The improved golf shaft should possess desired flexibility and necessary rigidity to permit the club to carry through and provide maximum flight to the ball.

SUMMARY OF THE INVENTION

An objective of the present invention is to provide a golf shaft possessing optimum flexibility, strength and durability.

Another objective of the present invention is to provide a golf shaft possessing a plurality of sides to accommodate different types of swings and speeds of swings of each individual golfer.

Another objective of the present invention is to provide a golf shaft possessing sides in the range of four to sixty four to provide variable types of swings to the golf shafts for different types of swings.

In accordance with an embodiment of the present invention, the present invention provides a golf club comprising a club head, a hand grip and a golf shaft. The golf shaft possesses four or more sides, the golf shaft having a relatively large diameter at the hand grip end and tapering to a relatively smaller diameter club head end.

In accordance with another embodiment of the present invention, the present invention provides a golf shaft for a golf club. The golf club comprising a club head and a hand grip. The golf shaft being tapered in the direction from hand grip to the club head, the golf shaft comprising a plurality of sides.

The golf club of the present invention possesses a number of advantages. The golf club of the present invention facilitates different degree of flexibility by varying the number of sides of the golf shaft. The varying degree of flexibility provides different types of swings and speeds of swings of each individual golfer, to produce a better, more accurate control. Further, as compared to the shafts of the prior art the shaft of the present invention provides enhanced provides enhanced torsional resistance at the tip. Moreover, the golf shaft of the present invention achieves this without degrading the bending stiffness of the shaft.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present invention, the needs satisfied thereby, and the objects, features, and advantages thereof, reference now is made to the following description taken in connection with the accompanying drawings.

FIG. 1 shows golf club according to an embodiment of the present invention;

FIG. 2 shows a sectional view of golf shaft according to an embodiment of the present invention;

FIG. 3 shows top view of cross sections of two golf shafts according to an embodiment of the present invention;

FIG. 4 shows the golf club according to another embodiment of the present invention; and

FIG. 5 shows the side view of the golf shaft according to an embodiment of the present invention.

Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Before describing in detail the particular golf shaft in accordance with an embodiment of the present invention, it should be observed that the present invention resides primarily in combinations of system components related to the device of the present invention.

Accordingly, the system components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.

In this document, relational terms such as ‘first’ and ‘second’, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. The terms ‘comprises’, ‘comprising’, or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by ‘comprises . . . a’ does not, without more constraints, preclude the existence of additional identical elements in the process, method, article, or apparatus that comprises the element.

FIG. 1 shows golf club 100 according to an embodiment of the present invention. The golf club 100 includes a handle 102, a hand grip 104, a golf shaft 106 and a club head 108. The handle 102 is used to hold the golf club 100 while hitting the ball through the hand grip 104. The golf shaft 106 possesses a plurality of sides and is tapered from handle 102 to the club head 108.

According to the preferred embodiment, the golf shaft 106 possesses four to sixty four sides. The golf club 100 having four sides being the stiffest and the golf club 100 having sixty four sides being the most flexible. The purpose of the different degrees of flexibility of each shaft is to accommodate the different types of swings and speeds of swings of each individual golfer, to produce a better, more accurate control.

According to another embodiment of the present invention, the golf shaft 106 of the present invention is two piece golf shaft combining metal and fiber/resin composite, in a manner as to produce a superior hybrid shaft which retains the well established advantages of both materials.

FIG. 2 shows a sectional view of golf club 100 according to an embodiment of the present invention. The golf club 100 includes the golf shaft 106, a club head 108 and a shaft cross section 106 a. In the present embodiment, the cross sectional shape of the golf club 100 is hexagonal and possesses six sides as shown by the shaft cross section 106 a.

FIG. 3 shows top view of cross sections of two golf shafts according to an embodiment of the present invention. The figure shows a golf shaft cross section 302 and a golf shaft cross section 304. The golf shaft cross section 302 is octagonal and the golf shaft cross section 304 is a polygon having fifteen sides. Accordingly, the octagonal golf shaft is stiffer than the golf shaft possessing fifteen sides.

FIG. 4 shows the golf club 100 according to another embodiment of the present invention. The golf club 100 of the present embodiment is hexagonal and is telescopic in nature. The golf shaft 106 is both telescopically collapsible and adjustable for use at any position between a fully extended position and fully collapsed condition.

Specifically, the golf shaft 106 includes three telescopic sections, a lower section 402, a center section 404, and an upper section 406, successively telescopic and received within one another, which permits the golf club 100 to collapse to a size approximately one third its fully extended length. More specifically, the upper end 408 of the lower section 402 is inserted into the lower end 410 of the center section 404, and the upper end 412 of the center section 404 is inserted into the lower end 414 of the upper section 406. The overall length of the shaft is decreased by fully inserting the lower section 402 further into the center section 404 and fully inserting the center section 404 into the upper section 406.

FIG. 5 shows the side view of the golf shaft 106 according to an exemplary embodiment of the present invention. In the illustration, two sides of a telescopic hexagonal shaft are visible. The figure depicts the tapering of the golf shaft 106 from the hand grip end of the golf club 100 to the club head end of the golf club 100. Side ‘AA’ represents the end of the golf shaft closer to the hand grip end of the golf shaft 106 and side ‘BB’ represents the end of the golf shaft 106 closer to the club head.

Various color and texture variations of the finished shaft are possible by proper use of pigments in the resin materials by appropriate use of pigments in the resin materials and by use of paints or other cosmetic techniques well known in the art.

In various preferred embodiments described herein, the range of flexibility exhibited by the sets of shafts that comprise each category, generally, increase in relation to the swing speeds and/or skill levels for which each category is optimized, wherein the range of flexibility accorded to each category increases as the corresponding swing speeds and/or skill levels for which such categories of shafts are optimized increase. The relative flexibility of each shaft that comprises each category of shafts can be measured using any method and metric known in the art.

Still further, the present invention provides sets of golf clubs that include a plurality of shafts that exhibit a range of flexibility, which are optimized in accordance with the methods and embodiments described herein. For example, the present invention provides golf club shafts that are optimized for (i) any of a plurality of swing speeds, (ii) golfers exhibiting any of a plurality of skill levels, or (iii) golfers exhibiting any specific combination of skill and swing speed.

Of course, the golf club shafts described and claimed herein can be made of steel, graphite, steel and graphite, or any other composition by itself or in combination with others known in the art to be useful in producing and/or designing golf club shafts. Furthermore, the shafts described and claimed herein can be manufactured and/or mass produced using any method known in the art today or discovered hereafter.

The golf shaft of the present invention possesses a number of advantages. The golf shaft of the present invention facilitates different degree of flexibility by varying the number of sides of the golf shaft. The varying degree of flexibility provides different types of swings and speeds of swings of each individual golfer, to produce a better, more accurate control. Further, as compared to the shafts of the prior art the shaft of the present invention provides enhanced provides enhanced torsional resistance at the tip. Moreover, the shaft of the present invention achieves this without degrading the bending stiffness of the shaft.

While the present invention has been described in connection with preferred embodiments, it will be understood by those skilled in the art that variations and modifications of the preferred embodiments described above may be made without departing from the scope of the invention. Other embodiments will be apparent to those skilled in the art from a consideration of the specification or from a practice of the invention disclosed herein. It is intended that the specification and the described examples are considered exemplary only, with the true scope of the invention indicated by the following claims. 

1. A golf shaft for a golf club, the golf club comprising a club head and a hand grip, the golf shaft being tapered in the direction from hand grip to the club head, the golf shaft having a plurality of sides.
 2. The golf shaft of claim 1, wherein the plurality of sides is in the range of four to sixty four.
 3. The golf club of claim 1, wherein the golf shaft comprises one of a metal, a resin, or a plastic.
 4. A golf shaft for a golf club, the golf club having a club head and a hand grip, the golf shaft being tapered in the direction from the hand grip to the club head, the golf shaft comprising four or more sides.
 5. The golf shaft of claim 4, wherein the golf shaft comprises one of a metal, a resin, or a plastic.
 6. A golf club comprising: a. a club head; b. a hand grip; and c. a golf shaft possessing four or more sides, the golf shaft having a relatively large diameter at the hand grip end and tapering to a relatively smaller diameter at the club head end.
 7. The golf club of claim 6, wherein the golf shaft is made from one of a metal, resin or a plastic.
 8. The golf club of claim 6, wherein the golf club is made from one of a metal or a resin. 